netty是在哪里检测有新连接接入的

新连接是怎么注册到NioEventLoop线程中的

Netty新连接接入处理逻辑

1.检测新连接
2.创建NioSocketChannel
3.分配线程及注册selector
4.向selector注册读事件

1.新连接检测

//检测连接
private void processSelectedKey(SelectionKey k, AbstractNioChannel ch) {
        NioUnsafe unsafe = ch.unsafe();
        if (!k.isValid()) {
            NioEventLoop eventLoop;
            try {
                eventLoop = ch.eventLoop();
            } catch (Throwable var6) {
                return;
            }

            if (eventLoop == this && eventLoop != null) {
                unsafe.close(unsafe.voidPromise());
            }
        } else {
            try {
                int readyOps = k.readyOps();
                if ((readyOps & 8) != 0) {
                    int ops = k.interestOps();
                    ops &= -9;
                    k.interestOps(ops);
                    unsafe.finishConnect();
                }

                if ((readyOps & 4) != 0) {
                    ch.unsafe().forceFlush();
                }

                if ((readyOps & 17) != 0 || readyOps == 0) {
                    unsafe.read();
                    if (!ch.isOpen()) {
                        return;
                    }
                }
            } catch (CancelledKeyException var7) {
                unsafe.close(unsafe.voidPromise());
            }

        }
    }

2.创建NioSocketChannel

new NioSocketChannel(parent,ch):入口
   AbstractNioByteChannel(p,ch,op_read)
       configureBlocking(false)&save op
       create id,unsafe,pipeline
   new NioSockectChannelConfig()
       setTcpNoDelay(true):禁止Nagle算法

2.1 Netty中的Channel的分类

NioServerSocketChannel
NioSocketChannel
Unsafe

2.2 Netty中channel层级关系

image.png

3新连接NioEventLoop分配和selector注册

3.1服务端Channel的pipeline构成

image.png

3.2ServerBootstrapAcceptor的功能

1.添加childHandler
2.设置options和attrs
3.选择NioEventLoop并注册selector

4.向selector注册读事件（NioSocketChannel读事件的注册）

通过传播channelactive方法，将客户端的读时间注册到selector